Vehicle airbag cover assembly

ABSTRACT

A vehicle airbag cover assembly, comprises a cover element and an electronic module comprising a light emitting element. The module is embedded in an at least partially transparent plastic material thus forming an integrated electronic module. The integrated module is arranged at the cover element such that an illumination from the at least one light emitting element is visible for a passenger when the airbag cover assembly is installed in a vehicle.

1. FIELD OF THE INVENTION

The present invention relates to a vehicle airbag cover assembly, thatallows the integration of light-emitting features to provide a passengerin the vehicle with informative and/or aesthetic illuminations.

2. TECHNICAL BACKGROUND

An airbag is a safety device for passenger vehicles utilizing aninflatable bag that deploys in case of an accident. The main componentsof any airbag are the flexible fabric bag, an inflation module and anairbag cover, which covers all these components in the interior of thevehicle. For a safe and reliable deployment of the airbag, the cover isusually provided with predetermined breaking points or lines that allowa rupturing of the cover element upon deployment of the airbag. Airbagsare used in various locations inside of the vehicle, like for example inthe steering wheel, in front of the passenger seat, in the A-pillar ofthe vehicle etc. For safety reasons it is very important that the airbagcover upon deployment of the airbag does not produce any dangerousdebris, like splintered elements.

In modern vehicles, the use of illumination inside of the passengercompartment serves to increase the comfort as well as the safety in formof for example safety warnings. In this context it would be desirable toalso provide airbag covers with such illumination features for aestheticand safety purposes. This is in particular true for the driver airbaginside of the steering wheel, as this airbag is in direct view of thedriver. By illuminating for example a logo of the vehicle manufacturer,which is typically centrally located on the cover of the driver airbag,a particularly pleasant effect can be created and the illuminationfeatures would be in the perfect position to be readily recognized bythe driver.

However, in the past it was not possible to integrate such anillumination feature in an airbag, respectively airbag cover, as thenecessary electronic components must be arranged in the deployment zoneof the airbag, so that upon deployment of the airbag these componentsare a safety risk. For this reason, up to now, illuminations of airbagcovers, although highly desirable for comfort and safety reasons, arenot available.

It is therefore one object of the present invention to overcome thedisadvantages of the art and to provide an improved airbag coverassembly with integrated illumination features. Other objects andadvantages of the invention will become apparent on reading thefollowing description.

The objects are solved by an airbag cover assembly in accordance withclaim 1 and a vehicle comprising such an assembly in accordance withclaim 15.

3. DETAILED DESCRIPTION OF THE INVENTION

Preferably, the above problems are solved by a vehicle airbag coverassembly, comprising a cover element and an electronic module comprisinga light emitting element. The module is embedded in a at least partiallytransparent plastic material, so that the module and the plasticmaterial form an integrated electronic module. The integrated electronicmodule is arranged at the cover element such that an illumination fromthe at least one light emitting element is visible for a passenger whenthe airbag cover assembly is installed in a vehicle.

By embedding the electronic module in plastic material, the variouscomponents of the module will not splinter upon deployment of theairbag. In other words, since the electronic module is completelyencapsulated by the plastic material the module will keep its integrityand does not break, so that no sharp or dangerous objects will fly intothe passenger compartment of the vehicle in case of an accident. Mostpreferably, the plastic material is injection molded over the module andpreferably covers all components of the module safely and completely.

Since the plastic material is at least partially transparent, the lightemitted from the module is still visible and it is thereby possible torealize comfort and safety features, which are in direct view of forexample the driver of the vehicle, when for example used in connectionwith the driver airbag. The illumination can for example be used to warnthe driver of an imminent collision by using a suitable warning light.

In a preferred embodiment, the integrated electronic module, and inparticular the plastic material thereof, forms a part of the surface ofthe cover element. This can be achieved by various means. For example,the cover element may comprise openings or apertures and the plasticmaterial is shaped such that portions of the plastic material protrudeinto these openings, respectively fill these openings, so that the outersurface of the cover element is essentially flush. As the skilled personwill recognize, this will lead to a very good visibility of anyillumination.

The airbag cover may be provided with at least partially transparentportions and/or openings and the integrated module may be arranged onthe rear side of the airbag cover, to at least partially cover thetransparent portions and/or openings. In this way, illumination derivingfrom the module can shine through these transparent portions, so thatthe illumination is visible for the passengers of the vehicle. The rearside of the airbag cover is the side which in installed condition facesaway from the passenger compartment. This contrasts with the front sideof the airbag cover, which is the surface of the cover facing theinterior of the passenger compartment.

Preferably, the integrated electronic module is configured to illuminatea logo of the vehicle brand (like a logo of the vehicle manufacturer ora specific logo of the vehicle model). In passenger vehicles the logo ofthe vehicle brand/model is typically arranged centrally on the cover ofthe driver's airbag. This is often the only place in the interior of thepassenger vehicle which shows a logo of the manufacturer and is veryimportant from a marketing viewpoint. Further, this central location isreadily visible for the driver of the vehicle and therefore an ideallocation for placement of additional safety features, such as theabovementioned use of light signals as warning signals for the driver.In the prior art, it was not possible to use this central location forsuch features, as the deployment of the airbag would almost inevitablybreak off parts of the necessary electronics, which then becomedangerous shrapnel flying through the passenger compartment. With thepresent invention, this problem is overcome by the safe embedding of thenecessary electronic components in an integrated electronic module.

In some embodiments, a logo may be integrated with the cover element,and/or a logo may be integrated with the integrated electronic module,and/or a logo may be provided in form of a separate component that isattached to the front surface of the cover element. To achieve anilluminated car manufacturer logo, the same may for example beintegrated with the cover element, in which case naturally at least someparts of the logo itself, or parts of the surrounding material aroundthe logo, must be transparent to the light emitted from the electronicmodule. Another possibility is to integrate the logo at least partiallywith the integrated electronic module itself, so that upon illuminationby means of the light emitting elements, the logo becomes illuminated aswell. Another option is to arrange the logo as a separate component atthe front surface of the cover element, as it is currently typicallydone with non-illuminated logos on the covers of the driver's airbag.Obviously, also in this case some form of transparency must be providedeither in the logo itself and/or the material surrounding the logo.

Preferably, the electronic module comprises a flexible substratecarrying the light emitting element. The flexible substrate preferablyfurther comprises electrical tracks and/or circuits that may be printedonto the substrate, e.g. by means of electrically conductive inks. Thisallows for a facilitated mounting on for example the rear side of thecover element and it improves the overall safety of the components.

In some preferred embodiments, the surface of the embedding plasticmaterial is at least partially covered with a foil or textile, whichcomprises transparent portions and essentially non-transparent portions.Such a foil or textile allows a very convenient way to realize variousforms, shapes and symbols to be illuminated. For example, the foil ortextile may be essentially non-transparent, and the transparent regionsare in the form of the manufacturer's logo. Another option is to use anessentially transparent foil or textile and to print the non-transparentportions onto the foil or textile. This allows the use of a printingprocess to realize complex shapes in a fast, reliable and cost-effectivemanner.

In another preferred embodiment, the electronic module may comprise aflexible substrate carrying the light emitting element(s) and theembedding plastic material may comprise at its surface protrudingportions that extend at least partially through openings in the coverelement. The upper surface of the embedding plastic material is in thisembodiment not flush but provided with protruding portions, that may forexample have any shape, but are preferably formed to resemble a symbol,letters, graphical icons or similar. Most preferably, the protrudingportions from at least part of a logo of the car manufacturer. Theflexible substrate is provided with electrical tracks or circuits andmay use a flexible plastic substrate for mounting the various electricaland electronical components. As materials for the substrate polyimide,PEEK or polyester films may be used. A flexible substrate offersadditional safety advantages in case of an airbag deployment compared toa rigid printed circuit board.

The (preferably flexible) substrate may comprise light reflectingstructures separate from the light emitting element(s) configured todirect light emitted from the light emitting element(s) essentiallyperpendicular to the plane of the substrate. The use of such lightreflecting structures allows a more flexible arrangement of the lightemitting elements and/or the directing of light emissions away from thesubstrate in basically all directions. It further allows to manufacturethe module relatively flat, which is important given the limited spacefor mounting the module with the airbag cover. Yet still further,another advantage is that by using such light reflecting structures,which are relatively inexpensive compared to the light emitting elementsthemselves, it is possible to direct the light emitted by a single lightemitting element into various directions, by for example redirecting thelight. In this context it can be advantageous to arrange at least someof the light emitting elements(s) to emit light essentially parallel tothe plane of the substrate. Preferably the cover element comprises atleast one predetermined breaking point allowing a rupturing of the coverelement upon deployment of the airbag. When provided with such apredetermined breaking point, it is recommended to arrange theintegrated electronic module at a certain distance from said breakingpoint for additional safety.

As discussed above, the present invention offers advantages when used inconnection with a driver's airbag. In other words when the coverassembly is a driver airbag cover assembly.

The plastic material may be injection-molded onto the electronic module.As the skilled person will understand, the plastic material embeddingthe electronic module should prevent or at least mitigate that upondeployment of the airbag parts of the electronic module break orsplinter off and become dangerous missiles due to the force of thedeploying airbag. By injection molding the plastic material a safeembedding can be achieved, such that the whole assembly of electroniccomponents and plastic material is one robust integrated part and allelements thereof are inseparably encapsulated by the plastic material.

As a suitable plastic material one or more of the following materialsmay be chosen: thermoplastic materials in general, silicon,thermoplastic elastomers, polymers, polyethylenes, polystyrene, PMMA(Polymethylmethacrylate), Polycarbonate (PC), polyimide, rubber orrubbery material.

Preferably, the integrated electronic module has an essentially flatconfiguration with a thickness of 2 to 10 mm, preferably 2 to 8 mm, morepreferably 2 to 7 mm and most preferably 2 to 5 mm. Thus, this assemblycan be made really thin such that it fits into the limited space in anairbag assembly, as for example on the rear side of the cover element ofthe airbag.

The present invention also relates to a vehicle, in particular passengervehicle, comprising an airbag cover assembly as disclosed above.

It is clear for the skilled person, that the above-described embodimentsare not mutually exclusive. It is for example possible to provide thecover element with openings into which protrusions of the plasticmaterial extend and at the same time to provide other portions of thecover element with transparent surfaces, so that the illumination effectis established partially by the protruding portions of the plasticmaterial and partially by the transparent regions of the cover element.Similarly, the skilled person will understand that if it is for exampledesired to illuminate a logo of the vehicle manufacturer one can realizethe logo partially by a protruding portion of the plastic material andpartially by suitably designed transparent and non-transparent regionson the surfaces of the plastic material and/or the cover element.

4. SHORT DESCRIPTION OF THE FIGURES

In the following, exemplary embodiments of the invention are describedwith reference to the figures.

FIG. 1 shows an electronic component for illuminating symbols orsurfaces according to the prior art;

FIG. 2 shows an airbag cover assembly in accordance with the inventionin a three-dimensional view;

FIG. 3 shows an embodiment of an integrated electronic module accordingto the invention in a partially cut view;

FIG. 4 shows another embodiment of an integrated electronic moduleaccording to the invention in a partially cut view;

FIG. 5 shows yet another embodiment of an integrated electronic moduleaccording to the invention in a partially cut view; and

FIG. 6 shows a further embodiment of an integrated electronic moduleaccording to the invention.

5. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows an electronic module 1 for illuminating surfaces or symbolsor similar according to the prior art. The module comprises a housing 3having a transparent cover 2. Inside of housing 3, a printed circuitboard (PCB) 4 is arranged onto which a number of LEDs 5 is mounted. TheLEDs 5 emit light which shines through the transparent cover 2. Such anassembly generally works well for a large number of applications, but itcan hardly be used inside of an airbag assembly, as upon deployment ofthe airbag and the rupturing of the airbag cover, pieces of the module 1may become loose, or break off, and will fly through the passengercompartment of the vehicle, potentially injuring passengers.

FIG. 2 shows a vehicle airbag cover assembly 10 in accordance with theinvention in a schematic three-dimensional view. The shown assembly 10is for a driver airbag of the vehicle and comprises a cover element 30and an integrated electronic module 20 i. Reference sign 11 indicatesmounting means, by means of which the cover assembly can be mounted tothe steering wheel, respectively steering column of the vehicle. As onecan take from FIG. 2 , the module 20 i forms a part of the surface ofthe cover element 30. To this end, the cover element 30 has anessentially circular opening or cut-out and the module 20 i has acorrespondingly shaped circular portion that fits into the opening. Aswill be described in more detail below, the portion of module 20 i thatforms part of the cover element 30 is at least partially transparent tovisible light, such that illumination from a light-emitting element ofthe module 20 i is visible for a passenger, when the airbag coverassembly 10 is installed in the vehicle.

FIG. 3 shows the airbag cover assembly 10 of FIG. 2 in a schematic,partially cut side view. The integrated electronic module 20 i comprisesan electronic module 20 having a number of LEDs 23, that are arranged ona flexible substrate 22. The substrate 22 is provided with electricconducts 25, to connect the module 20 with a power supply and controlelectronics of the vehicle. The module 20 with all its components, likeLEDs 23 and substrate 22, is embedded in a translucent plastic material21, thereby forming the integrated electronic module 20 i. The plasticmaterial 21 is preferably injection molded over substrate 22 and LEDs 23for a complete and safe encapsulation of the various components of themodule. The substrate 22 is further provided with electrical tracksand/or other electrical and electronic components (not shown).

As one can take from FIG. 3 , the integrated module 20 i is arranged atleast partially on the front side of the cover element 30 and thus formsa part of the surface of the cover element. The cover element isprovided with openings or apertures to allow a fixation of the moduleand for introducing the electrical conducts 25 of the substrate. Theplastic material 21 has integrally formed mounting means 26 that fitinto the apertures in the cover element 30. On top of the plasticmaterial 21 a decorative foil 24 is arranged that may be provided withtransparent and nontransparent portions so that upon illumination by theLEDs 23 a decorative pattern is illuminated. The decorative pattern mayfor example show a logo of the car manufacturer.

FIG. 4 shows another embodiment of an airbag cover assembly 10′. In theembodiment of FIG. 4 , the electronic module 40 is mounted on the rearside of the cover element 30. The module comprises a flexible substrate42, onto which a number of LEDs 43 are mounted. The module 40 isembedded in plastic material 41 thus forming an integrated electronicmodule 40 i. The LEDs 43 are arranged to emit light essentially parallelto the plane of the substrate 42. The light from the LEDs 43 isredirected essentially perpendicular to the plane of the substrate 42 bymeans of a light reflecting structure 47. The embedding plastic material41 comprises at its outer surface protruding portions 44, that extendthrough openings 31 in the cover element 30. In the shown embodiment,the protrusions 44 protrude to some extent out of the openings 31 butmay also be configured to be flush with the front surface of cover 30 oreven extent only partially into the opening 31.

As with the other embodiments, the plastic material 41 is preferablyinjection molded to embed the various components of the electronicmodule, like for example the LEDs 43, substrate 42 and reflectivestructures 47. By arranging the LEDs 43 such that the light is emittedessentially parallel to the plane of the substrate 42 it is possible tocreate various illumination profiles and it is possible to save costs,as the reflective structures may be used to redirect light from a singleLED into various directions, so that a single LED can be used to emitlight in different directions. The reflective structure 47 is shown as aprotrusion of the substrate but also different forms are possible. Thereflective structure can also be a separate component, that is mountedto the otherwise flat substrate.

The protrusions 44 can be arranged in various shapes to represent forexample symbols, numbers, letters, etc., or preferably a logo of the carmanufacturer. One advantage of this embodiment is, that by means of theprotrusions 44 not only a visual but also a haptic feature can berealized.

FIG. 5 shows yet another embodiment of a vehicle airbag cover assembly10″. The integrated electronic module 50 i is similar to the module ofthe embodiment of FIG. 4 . A number of LEDs 53 is arranged to emit lightessentially parallel to the plane of the flexible substrate 52. A numberof reflective structures 57 are mounted on the surface of the substrate52 to direct light away from the substrate surface in directionsessentially towards openings 31 provided in the cover element 30. In theembodiment of FIG. 5 , the module 50 i is mounted on the rear side ofthe cover element 30, that means the surface facing away from thepassenger compartment, when the airbag cover assembly is installed in avehicle. Instead of protrusions that are integrally formed with theplastic material 51 of the module 50 i, the front surface of the coverelement 30 is provided with a separate component 59 that in the shownembodiment resembles a logo of the car manufacturer. This alternativeallows more flexibility in shaping the separate component and itsimplifies the manufacturing process of the integrated module 50 i.

The embodiment of FIG. 5 further comprises mounting means 56 in the formof protrusions integrally formed with the plastic material 51. Themounting means 56 extend into corresponding apertures on the rear sideof cover element 30.

FIG. 6 shows yet another embodiment of an airbag cover assembly 10″. Theelectronic module 60 comprises a substrate 62 having several LEDs 63mounted thereon as well as a reflective structure 67 in form of areflective foil that is glued to the surface of the substrate. All thecomponents of the electronic module 60 are encapsulated by plasticmaterial 61 thus forming an integrated electronic module 60 i. Theintegrated module is arranged in an opening of the cover element 30 andthus forms a part of the surface of the cover element. A decorativetextile 64 is arranged on the top surface of the integrated module 60 icovering the same as well as the surface of the cover element 30. On therear side of the decorative textile some non-transparent portions 65 areprinted, so that light emitted from the LEDs 63 is essentially onlyvisible through those portions of the textile 64, that are not providedwith printed portions 65. It is readily apparent for the skilled person,that this embodiment allows a great flexibility in designing theilluminated areas.

It should be understood that the invention is not limited to singleembodiments described herein, but that the embodiments are onlyexemplary to facilitate understanding of the invention. It is inparticular possible to combine the aspects of the various embodimentsand use e.g. protruding portions, separate elements, openings in thecover element, decorative foils, etc. all in one single assembly, ifthat should be necessary or desired. For example, the shown arrangementof a rear mounted module 40 i with protrusions 44 shown in FIG. 4 can berealized on some portions of the cover element, while on other portionsof the same cover element the solution of FIG. 3 is realized, etc.

REFERENCE SIGNS

-   1 electronic module (prior art)-   2 transparent cover-   3 housing-   4 PCB-   5 LED-   10, 10′, 10″, 10′″ airbag cover assembly-   11 mounting means-   20, 40, 50, 60 electronic module-   20 i, 40 i, 50 i, 60 i integrated electronic module-   21, 41, 51, 61 plastic material-   22, 42, 52, 62 (flexible) substrate-   23, 43, 53, 63 LED-   24 decorative foil-   25 electrical conducts-   26, 46, 56 mounting means-   30 cover element-   31 opening-   32 mounting apertures-   47, 57, 67 light reflecting structure-   59 separate component-   64 decorative textile-   65 non-transparent portions

1. A vehicle airbag cover assembly, comprising: a cover element and anelectronic module comprising a light emitting element, which module isembedded in a at least partially transparent plastic material thusforming an integrated electronic module, whereby the integrated moduleis arranged at the cover element such that an illumination from the atleast one light emitting element is visible for a passenger when theairbag cover assembly is installed in a vehicle.
 2. The vehicle airbagcover assembly according to claim 1, wherein the plastic material formsa part of the surface of the cover element.
 3. The vehicle airbag coverassembly according to claim 1, wherein the airbag cover element isprovided with at least partially transparent portions and/or openingsand the integrated module is arranged on the rearside of the airbagcover element at least partially covering the transparent portionsand/or openings.
 4. The vehicle airbag cover assembly according to claim1, wherein the integrated electronic module is configured to illuminatea logo of the vehicle brand.
 5. The vehicle airbag cover assemblyaccording to claim 1, wherein the logo is integrated with the coverelement, and/or wherein the logo is integrated with the integratedelectronic module, and/or wherein the logo is provided in form of aseparate component that is attached to the front surface of the coverelement.
 6. The vehicle airbag cover assembly according to claim 1,wherein the integrated electronic module comprises a flexible substratecarrying the light emitting element and the surface of the embeddingplastic material is at least partially covered with paint, a foil ortextile, which comprises transparent portions and essentiallynon-transparent portions.
 7. The vehicle airbag cover assembly accordingto claim 1, wherein the non-transparent portions are printed onto thefoil.
 8. The vehicle airbag cover assembly according to claim 1, whereinthe integrated electronic module comprises a flexible substrate carryingthe light emitting element and the embedding plastic material comprisesat its surface protruding portions that extend at least partiallythrough openings in the cover element.
 9. The vehicle airbag coverassembly according to claim 1, wherein the flexible substrate compriseslight reflecting structures separate from the light emitting element(s)configured to direct light emitted from the light emitting element(s)essentially perpendicular to the plane of the substrate.
 10. The vehicleairbag cover assembly according to claim 1, wherein at least some of thelight emitting elements(s) are arranged to emit light essentiallyparallel to the plane of the substrate.
 11. The vehicle airbag coverassembly according to claim 1, wherein the cover element comprises atleast one predetermined breaking point allowing a rupturing of the coverelement upon deployment of the airbag.
 12. The vehicle airbag coverassembly according to claim 1, wherein the cover assembly is a driverairbag cover assembly.
 13. The vehicle airbag cover assembly accordingto claim 1, wherein the plastic material is injection-molded onto theelectronic module and/or wherein the plastic material is chosen from thegroup of: thermoplastic materials in general, silicon, thermoplasticelastomers, polymers, polyethylenes, polystyrene, PMMA,(Polymethylmethacrylate), Polycarbonate (PC), polyimide, rubber orrubbery material.
 14. The vehicle airbag cover assembly according toclaim 1, wherein the integrated electronic module has an essentiallyflat configuration with a thickness of 2 to 10 mm.
 15. The vehicle, inparticular passenger vehicle, comprising an airbag cover assemblyaccording to claim
 1. 16. The vehicle airbag cover assembly according toclaim 1, wherein the integrated module has an essentially flatconfiguration with a thickness of 2 to 8 mm.
 17. The vehicle airbagcover assembly according to claim 1, wherein the integrated module hasan essentially flat configuration with a thickness of 2 to 7 mm.
 18. Thevehicle airbag cover assembly according to claim 1, wherein theintegrated module has an essentially flat configuration with a thicknessof 2 to 5 mm.